Gov. Jerry Brown announced a state of emergency Friday that has been all but official for weeks: California is in a drought.

Brown urged Californians to reduce water use by 20 percent, saying “we’re facing perhaps the worst drought that California has ever seen since records began being kept about 100 years ago.”

The emergency declaration comes as the state suffers through dry conditions for a third straight year. It follows weeks of consideration by the Brown administration amid pressure from lawmakers and water officials to act.

The Democratic governor had suggested for days that he was close to declaring the emergency, a measure considered significant to focusing the attention of the public and federal officials who could accelerate some relief efforts.

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In declaring an emergency, Brown directed state agencies to hire more seasonal firefighters, use less water and prepare a water conservation public awareness campaign.

Brown’s appeal to residents to reduce water consumption is voluntary, but he suggested at a news conference in San Francisco that the state could impose mandatory restrictions if the drought persists.

“As we go down the road – you know, January, February, March – we will keep our eye on the ball and intensify, even to the point of mandatory conservation,” Brown said. “But we’re not going to do that quite yet.”

California is entering one of the driest winters on record after two dry years already parched the state. Many reservoirs are depleted, and streams and rivers are running low.

Officials at Merced Irrigation District have said the drought situation in Merced County is nothing less than dire, and the outlook is unprecedented.

Mike Jensen, MID spokesman, said the district expects the irrigation season to be short and possibly include as little as an inch of water per acre for MID growers. MID will be discussing the water outlook at its Tuesday board meeting and is planning additional meetings to discuss the water crisis with growers in the coming weeks.

“We are committed to doing all that we can to be of assistance to our growers. However, when there is no snow or rain, there is only so much that can be done,” Jensen said.

In 2011, MID experienced so much inflow to Lake McClure that it released 1 million acre feet of water from storage downstream to the ocean. In more simple terms, MID drained and refilled Lake McClure in 2011, Jensen said.

Following that wet year, 2012 and 2013 both proved to be dry years. So far, Jensen said the 2013-14 water year is shaping up to be a third dry year, and the driest year on record.

Lake McClure currently holds around 226,000 acre feet and is at 22 percent capacity. Without a drastic change in weather, MID’s on track to reach minimum pool, 115,000 acre feet, this summer/irrigation season, Jensen said. That would mean all irrigation operations would halt and state agencies would have discretion over how the remaining limited supply would be used for wildlife and stream flows.

The U.S. Climate Prediction Center predicts below-average precipitation in California for the rest of January and all of February, according to figures released Thursday, and the National Weather Service predicts no precipitation in the Sierra Nevada, which supplies much of the state’s water, during the next seven days.

The dry weather is due to high pressure off the coast that is preventing storm systems from developing, said Brad Pugh, a meteorologist with the U.S. Climate Prediction Center.

“We’re expecting drought conditions across California to intensify over the next few months,” Pugh told The Bee.